A woman wearing an explosive suicide vest blew herself up today as heavily armed police tried to storm a suburban Paris apartment where the suspected mastermind of last week's attacks was believed to be holed up, police said.

They said two people were killed and seven people were arrested in the standoff, which began before dawn and was continuing more than four hours later. One person remained holed up in the apartment.

A senior police official said he believed Abdelhamid Abaaoud, a Belgian Islamic State militant, was inside the apartment in the Paris suburb of Saint-Denis with five other heavily armed people. The official, who was not authorized to be publicly named according to police rules but is informed routinely about the operations, said scores of police stormed the building and were met with unexpectedly violent resistance.

Another police official not authorized to be publicly named because of police rules said four police officers were injured. No hostages were being held.

The Paris prosecutor's office said SWAT teams arrested three people in the apartment. It said they haven't been identified yet. Another man and woman were detained near the apartment, the office said in a statement.

Investigators have identified 27-year-old Abaaoud, a Belgian of Moroccan descent, as the chief architect of attacks in Paris, which killed 129 people and injured 350 others.